Continuous mining machine and control system therefor



s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Oct. 5, 1965 15 Sheets-Sheet 1 Filed Sept. 4, 1959 H T T 5 A Y K Y B B S. C. MOON Oct. 5, 1965 CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR l5 Sheets-Sheet 2 Filed Sept. 4, 1959 nmw WUM

Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet s IN V EN TOR; STEEL: NG C. Moo BY DECEF) SE0,

KATHAEYNE M MooN, BY HDMIIWSTEATE/ x,

Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 4 PPM Em w MW u NR M INVENTOR; STERLING Cv MooN,

BY DECEA 5E0,

KATHAEYNE M. MooN,

HpM/msTEA /e/x,

PUG

Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 5 o [If B E I i: 8 BF HEAD SEPARATE Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 6 Fig. 6

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INVENTOR; I sTERLJNG C. MOON 233/ E 233 5,, DECEBSED,I 23G 235 237 KATHAEYNE M. MooN, BY flDM/N/STEATF/X M Y/Q T Y.

Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 7 Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 8 Fig 11 l 2 fiq- 1% 326 320 357 [Q 304 I H 340 \L Hk 34 324 E iG x 285 INVENTOR,

,M 26g BY s -Efi f g KATHAEYNE MMooN, 5y fiDM/N/STE/TFE/X,

Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 9 UPPER RIGHT CUTTER ARM LOWER RIGHT CUTTER ARM UPPER LEFT CUTTER ARM K IN VEN TOR, Ln STERLING C.MOON, m BY DECEASED, KATHAEYNE M. MooN,

5 HDMINISTEHTE/X W HTT'Y Oct. 5, 1965 CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 S. C. MOON 15 Sheets-Sheet 10 W Law. HTTY Oct. 5, 1965 Filed Sept.

s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR 4, 1959 15 Sheets-Sheet 11 KATHAEYNE M, MOON, By HDM/N/STEHTE/X,

Oct. 5, 1965 s. c. MOON 3,210,122

CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 12 Fj/s q J INVENTOR 5TEELING C. MooN,

KATHAEYNE M. MOON, 5y HDM/N/STEHTE/ x,

W HTT Y.

S. C. MOON Oct. 5, 1965 CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet l3 N) WEN bR E 0M5 I I l T m 23w 23m HESW m? 01w u wmm w. o mm? 7 5v. Wvq Um? M052 R zou mu mu Linn. T h 1 mW wmcmzng 5 Y 2%? 62 mo 5m m m fiwmw 5 EC: 3 A o :1v POE mm 56 I2 m3 Emmi? wmbz mums? WIN PIN /l\ 5v mmw mmw rvO V W I o w 1 n5 w S. C. MOON Oct. 5, 1965 CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Filed Sept. 4, 1959 15 Sheets-Sheet 15 ON LIGHTS 40M AUTO. AUTO. 486@482 BACK HEAD TILT LOWER HEAD RAISE HEAD SEPARATE 1 NJ, 1V. wqw w 85 R 2 my? A o mCmMm I VGDEW m 3 E E AH l T W E 5 A YKY 5 5 United States Patent O 3,210,122 CONTINUOUS MINING MACHINE AND CONTROL SYSTEM THEREFOR Sterling C. Moon, deceased, late of Dublin, Ohio, by Katharyne M. Moon, administratrix, Dublin, Ohio, assignor, by mesne assignments, to Jeffrey Galion Manufacturing Company, a corporation of Ohio Filed Sept. 4, 1959, Ser. No. 838,110 12 Claims. (Cl. 299-30) The instant invention relates to continuous mining machines for the mining of coal, which are adapted to be continuously advanced into the mine face to remove the coal therefrom, and which include conveying means to carry the mined material away from the mine face and to discharge the same at the rear of the machine, to permit the continuous advance of the mining machine into the face. More particularly the instant invention relates to a continuous mining machine in which there is provided a system for sensing the advance of the mining machine into the selected material in the mine face, which is the coal, and the mining machine includes a control system for operating the mining machine from a position that is remotely located with respect to the mine face and the mining machine, the remote control system including the sensing system, and the mining machine being operated from the remote location in accordance with the signals which indicate the course of advance of the mining machine into the selected material.

It is a prime object of this invention to provide a continuous mining machine provided with a control system for the operation of the mining machine from a position that is spaced with respect to the mine face and the mining machine.

It is still another object of the instant invention to provide a continuous mining machine which includes hydraulic mechanisms for operating the machine, and hydraulic controls for said hydraulic mechanisms in which there is provided means for operating said hydraulic controls from a position remotely located with respect to the mining machine.

It is a further object of the instant invention to provide a continuous mining machine including a hydraulic system for operation of the mining machine, and an electrical control system for operation of the hydraulic system, in which the electrical system includes controls which may be located at a position remotely disposed with respect to the mining machine.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings:

FIGS. 1A and 1B together are a side elevational view of a continuous mining machine embodying the instant invention;

FIGS. 2A and 2B together are a plan view of the continuous mining machine of FIGS. 1A and 1B;

FIG. 3 is an elevational view of the continuous mining machine showing the mining heads and the hydraulic mechanisms for adjusting the same;

FIG. 4 is a front elevational view of the mining heads of the mining machine showing the disposition of the mining devices;

FIG. 5 is a diagrammatic illustration of the hydraulic system for the mining machine of this invention;

FIGS. 6, 7 and 8 are sectional views of control valves of the hydraulic system of FIG. 5;

FIG. 9 is a sectional view of a convey-or reversing valve for the hydraulic system of FIG. 5;

FIG. 10 is a partial sectional view of a volume control valve for the hydraulic system of FIG. 5;

e Ce FIG. 11 is a sectional view of a four-unit valve for the hydraulic system of FIG. 5;

FIG. 12 is a sectional view of the four-unit valve taken on the line 12-12 in FIG. 11;

FIGS. 13 and 14 are sectional views of the four-unit valve showing different positions thereof;

FIGS. 15A to 15F together form a diagrammatic illustration of the electrical system for the continuous mining machine of this invention;

FIG. 16 is a plan view of the face of the control box embodying the electrical controls for the continuous mining machine of this invention; and

FIG. 17 is a side elevational view of the top of the control box shown in FIG. 15.

The instant invention relates to continuous mining machines, particularly such as are adapted to be used in the mining of coal in underground operations, or in other mining operations in which the mining machine is adapted to be advanced into the ground. Customarily the controls for such machines are placed at an operators station at the side of the machine, and the operator of the machine accompanies it as it advances into the mine face, it being understood that it is a characteristic mode of operation of such a continuous mining machine that it forms a room or tunnel in the mine as it advances into the mine face, which room or tunnel is generally of greater dimension than the overall transverse dimensions of the machine, thereby providing room for the operator, and also providing room for backing the machine out of the room or tunnel and permitting it to be maneuvered into position to advance into another mine face.

It is recognized that there are certain dang'ers inherent in coal mining operations. It is accordingly customary to follow prescribed procedures for insuring the safety of those engaged in the coal mining operation. The inherent dangers connected with the mining of the coal are further reduced by the provision of apparatus for removing the coal from the mine face without requiring the proximate presence of a machine operator at the machine. In accordance with the instant invention there is provided a continuous mining machine which is adapted for coal mining operations, and which includes a sensing system for sensing the material in the mine face and providing signals indicating the course of advance of the mining machine relative to the location of the coal in the mine face, so that the course of advance of the mining machine may be guided accordingly, to keep the mining machine in the coal seam. The continuous mining machine of this invention further includes a control system in which the sensing devices provide signals at a position remotely located with respect to the mining machine that indicate the advance of the mining machine, and controls at that remote position by which the mining machine may be operated.

Referring to the drawings, FIGS. 14, there is illustrated therein a continuous mining machine 30 embodying the instant invention, and comprising a main frame 31 supported on a pair of endless crawler traction treads 32, 33 disposed at opposite sides of the main frame 31. The continuous mining machine 30 is propelled in forward or reverse directions by the crawler traction treads 32, 33, and may be steered by operating the crawler traction treads 32, 33 at ditierent speeds. The crawler traction treads 32, 33 are operated by individual hydraulic motors 34, 35, respectively, which are supported in the main frame 31. An identical mechanical drive extends between each of the hydraulic motors 34, 35 and the respective crawler traction treads 32, 33 for driving the latter. The drives to the crawler traction treads 32, 33 each comprises a pinion 0 36 driven by a hydraulic motor 34, 35 and driving a gear 37 which, in turn, drives a worm and worm wheel 38, the latter driving a pinion 39 which drives gear 40 that is co-axially mounted on a shaft with a drive sprocket 41 that is engaged with a crawler traction tread 32, 33 to drive the latter. The operation of each of the hydraulic motors 34, 35. may be reversed for driving the crawler traction treads 32, 33 in reverse, as when backing the continuous mining machine 31 away from a mine face. Also, the rate of delivery of hydraulic fluid to each of the motors 34, 35 may be independently varied to drive the crawler traction treads 32, 33 at different speeds for steering the continuous mining machine 30.

At the forward end of the continuous mining machine 30 there is a forwardly extending support 45 that is pivotally mounted on the main frame 31 on laterally extending pins 46. The support 45 extends forwardly from the main frame 31 along the floor 47 of the mine, with the support 45 being inclined downwardly in a forward direction, as best seen in FIG. 3.

The support 45 carries a lower mining head 43 and an upper mining head 49, which are disposed in substantial vertical alignment one above the other. The lower mining head 48 is pivotally connected to the support 45 by laterally extending pins 50. The upper mining head 49 is supported on the lower head 48 and includes depending guides 51 at the opposite sides thereof, which are engaged with tracks 52 on the lower mining head 48 for guiding the movement of the upper mining head 49 upwardly and downwardly relatively to the lower mining head 48-.

A double acting hydraulic cylinder and piston mechanism 55 is connected between the main frame 31 and the support 45 and is operative to raise and lower the support 45 by swinging the same upwardly and downwardly on the pivot pins 46. A double acting cylinder and piston mechanism 56 is connected between the main frame 31 and the lower mining head 48, and by operation of the cylinder and piston mechanism 56 the lower mining head 48, as well as the upper mining head 49 which is supported on the lower mining head 48, are tilted forwardly and rearwardly on the axis of the pivot pins 50. A third cylinder and piston mechanism 57 is connected between the lower mining head 48 and the upper mining head 49, for raising and lowering the latter relatively to the lower mining head 48.

The lower mining head 48 comprises a gear box 58 that extends laterally across the forward end of the continuous mining machine 30. A plurality of transversely aligned shafts 59 extend forwardly from the gear box 58, there being five shafts 59 in the disclosed embodiment of the invention. A radially extending cutter arm 60 is secured to each shaft 59. Each cutter arm 60 comprises integral bit holders 61, each of which is adapted to receive a plurality of forwardly extending bits 62. Within the gear box 58 there is enclosed a train of gears for rotating all the shafts 59 simultaneously, and in timed relation to each other. As seen in FIG. 4, the cutter arms 60 have different circumferential positions. The two cutter arms 60 at the left side and the cutter arm 60 at the center of the mining head 48, as seen in FIG. 4, are rotated in a counterclockwise direction, while the two cutter arms 60 at the right side of the mining head 48 are rotated in a clockwise direction. The cutter arms 60 are each rotated at the same speed, and are disposed in different selected circumferential positions so that there is no interference of the cutter arms 60 with each other during the simultaneous rotation thereof.

The upper mining head 49 includes a gear box 63, which also encloses a gear train for rotating a plurality of transversely aligned shafts 64 that project forwardly from the front of the gear box 63. In the illustrated embodiment of the invention the upper mining head 49 is provided with ten shafts 64, each of which has secured thereto a radially extending cutter arm 65. Each cutter arm 65 includes integral bit holders 66 for the reception of forwardly extending mining bits 67. The five cutter arms 65 at the left side of the upper mining head 49, as viewed in FIG. 4, are rotated in a counterclockwise direction, and

the five cutter arms at the right side of the upper mining head 49 are rotated in a clockwise direction. All of the cutter arms 65 are rotated simultaneously at the same speed by the gears within the gear box 63, and are placed in different circumferential positions on the respective shafts 64, to avoid any interference between the cutter arms 65 during the simultaneous rotations thereof.

As illustrated in FIG. 4, the upper mining head 49 is separated or raised with respect to the lower mining head 48, for mining a maximum height of material from the mine face. The cutter arms 60, 65 on the respective mining heads 48, 49 each operate in circular paths which are overlapping. The cutter arms 60, 65 are advanced into the mine face by the operation of the crawler traction treads 32, 33 advancing the whole mining machine 30 forwardly. As the mining bits 62, 67 are brought into the mine face, these bits operate to cut and break the material out of the mine face. The circular paths of th cutter arms 60, 65 cumulatively define a mine face area from which material is removed in the mining operation. As seen in FIGS. 2 and 4, the laterally outermost cutter arms 60a, 60b, 65a, 65b at each side of the mining machine 39, extend laterally beyond the maximum lateral dimension of the mining machine 30, whereby there is produced as result of the mining operation a room or tunnel which is wider than the mining machine 30. Each of the cutter arms 60, 65 is an eccentric element extending to only one side of its shaft 59, 64, respectively, whereby upon rotation of the cutter arms 60, 65, the laterally outermost cutter arms 60a, 60b, 65a, 65b may be withdrawn from the sides of the tunnel or mine room, and disposed in positions lying within the transverse dimensions of the mining machine 30. The cutter arms 60a, 60b, 65a, 65b thus being moved to positions out of contact with the side walls of the mine room or tunnel, it is possible to freely maneuver the mining machine 30.

The forward end of the support 45 includes a transversely extending blade 70 which is adapted to be disposed on the floor 47 of the mine behind the lower cutter arms 69. Since the cutter arms 60 operate in circular paths, they form cusps of material in the mine floor 47, and the blade 70 operating behind the cutter arm 60 removes these cusps from the floor 47, leaving the latter relatively smooth and level for the advance of the crawler traction treads 32, 33 thereover.

The forward end of the main frame 41 supports a pair of electric motors 71, 72 for driving the lower mining head 48 and the upper mining head 49, respectively. The drive from the motors 71, 72 is delivered to a gear case 73 which combines the power of the motors 71, 72. A

universal jointed drive shaft 74 extends from the gearcase 73 to the lower mining head 48, and a second universal jointed drive shaft 75 extends from the gear case 73 to the upper mining head 49. The drive shafts 74, 75 each include telescoping sections to permit adjustment of the mining heads 48, 49 as previously described.

The support 45 also carries one end of an endless chain conveyor 78, which is guided anound an idler sprocket assembly 79 at the forward end of the support 46. The conveyor 78 extends rearwardly from the forward end of the support 45, through the main frame 31 of the mining machine 30, as best seen in FIG. 1, and terminates at the rear end of the mining machine 39, at which point the conveyor 78 discharges the mined material. The conveyor 78 comprises two individual chain conveyors arranged side by side and each including oppositely disposed endless drive chains 80, to the links of which there are secured a plurality of transversely extending flights 81, which are adapted to sweep the mined material over the bed. 82 of the conveyor 78. The endless chain conveyor 78 is driven by a hydraulic motor 83 driving gears 84 which, in turn, drive a dual sprocket 85 that is connected by a chain drive 86 to dual sprockets 87, which are coaxially mounted on the driven shaft 88 with chain driving sprockets 89 that are engaged with the chains 80 for driving the latter.

The rotation of the cutter arms 65 of the upper mining head 49 is in such directions as to sweep the mined material towards the center of the mining machine 30. Similarly, the direction of rotation of the two outer cutter arms 60 at each end of the lower mining head 48 is in such directions as to sweep the mined material in towards the center of the mining machine 30. As the cutter arms 60, 65 are advanced into the mine face, the blade 70 works along the mine floor to remove the cusps left between the cutter arms 60, and also works its way into the material mined by the cutter arms 60, 65 to guide this material upwardly onto the support 45 to be received by the conveyor 78 and to be carried rearwardly thereby to the rear end of the mining machine 30 for discharge of the mined material therefrom. Since the mined material is carried away from the area of the mine face as it is mined, the advance of the cutter arm 60, 65 is not impeded and the mining operation may be carried on continuously. At each side of the lower mining head 48 there is provided a pivoted gathering guide 90, which also works to crowd the mined material in towards the center of the mining machine 30, to be received by the conveyor 78 for carrying this material away from the mine face.

It is a characteristic of coal that it is jound in the ground in seams which lie in relatively level planes. The coal may vary in thickness within a given seam, and the seam may rise and descend within the ground. Therefore it is customary for the operator of a continuous mining ma chine to view the face of the mine in which the mining machine is working to thereby visually determine whether the mining machine is following the coal seam. The mining heads 48, 49 are adjustable in a vertical direction relatively to each other for the purpose of adjusting to varying heights of coal in the coal seam. Thus where the coal seam is found to increase or decrease in height, the upper mining head 49 is elevated or lowered by means of the heads separating cylinder and piston mechanism 57, so that the vertical reach of the cutter arms 60, 65 is substantially equal to the height of the coal seam in which the machine is working. When the coal seam is found to drift upwardly or downwardly, the mining heads 48, 49 can be tilted either forwardly to operate the mining machine in a descending path, or the mining heads 48, 49 can be tilted backwardly to follow the coal scam in an ascending path, the tilting of the mining heads 48, 49 being accomplished by use of the tilting cylinder and piston mechanism 56. As a further adjustment in following the ascending or descending path of the coal seam, the support 45 and the mining heads 48, 49 carried thereby, can be raised by means of the raise cylinder and piston mechanism 55.

Above and below the coal seam there is generally found material which is relatively harder than the coal, such as rock or shale. Ideally, it is desired that the cutter arms 60, 65 do not enter the relatively harder material which is found above and below the coal seam, for the reason that this material is waste as far as the coal mining operation is concerned, and any such material removed from the mine face with the coal must later be separated from the coal product. Also the operation of the cutter arms 60, 65 in material that is relatively harder than coal produces excessive wear on the mining bits 62, 67, thereby severely reducing the life thereof, and making necessary more frequent replacement of the bits, which of course interrupts the mining operation and is therefore undesirable.

With the continuous mining machine embodying the instant invention it is intended to make unnecessary visual observation of the mine face, and for this purpose the cutter arms 60, 65 include sensing means for the purpose of sensing the course of advance of the mining machine, and more particularly the advance of the mining bits 62, 67 of the cutter arms 60, 65, respectively, into material that is relatively harder than the coal. The sensing means is included in a signaling system so constructed that it provides signals at a location remote from the mining face indicating the advance of the mining machine into material that ;is relatively harder than the coal. These signals are provided continuously during the operation of the cutter arms 60, 65 at a remotely located station at which all the controls for the mining machine 30 are located, as will be described in greater detail hereinafter, thereby making it unnecessary for the machine operator to take a position immediately adjacent the mining machine when the signals provided by the signaling system indicate that the mining machine is advancing into material relatively harder than coal, the mining heads 48, 49 are adjusted as previously described to move the mining bits 62, 67 back into the coal seam, such adjustment being made in accordance with the signals of the signal-ing system. Similarly, the limits of the coal seam may be located by adjustment of the mining heads 48, 49. During such exploratory adjustment the signaling system will indicate the entry of the mining bits 62, 67 into material other than coal, whereupon the mining heads 48, 49 may-be adjusted back to just clear the material other than coal, and the mining operation will proceed with only the removal of coal from the mine face.

As seen in FIG. 4, the cutter arms 60, 65 remove material from a determinate area 91 of the mine face, which is defined by the cumulative rotary sweep of the several cutter arms 60, 65 in the lower and upper rows of cutter arms respectively. The limits of the determinate area 91 of the mine face from which the material is removed are defined by the two outermost lower cutter arms a, 60b of the lower mining head 48, and by the two outermost cutter arms a, 65b of the upper mining head 49. Considering that the coal is found in laterally extending seams which are of a fairly regular nature, it is suflicient in sens ing the location of the coal seam to perform this sensing function at the limits of the determinate mine face area 91 from which the coal is removed by the cutter arms 60, 65. Accordingly, the sensing devices are incorporated in each of the cutter arms 60a, 60b, 65a, 65b. Since it is merely necessary to sense the material of the mine face at the limits of the determinate area 91 of the mine face from which the coal is removed, the sensing devices in the cutter arms 60a, 60b, 65a, 65b each operates in a quadrant which is coextensive with a corner of the determinate mine face area 91 defined by the cumulative sweep of all the cutter arms 60, 65.

In the operation of the continuous mining machine 30 embodying the sensing devices in the several cutter arms, if the cutter arm 65a senses material other than coal in the mine roof, the upper cutter head 49 can be lowered relatively to the lower cutting head 48 to thereby get below the relatively harder material, so that the mining machine in its continued operation will be operating solely in coal. Upon continued operation of the mining machine it may be found that the disposition of the relatively harder material in the roof of the mine indicates that the coal seam is drifting downwardly, which will call for a forward tilting of the mining heads 48, 49 to operate the mining machine in a descending path. Depending on the location of the coal seam as determined by the several sensing devices, it may be found that a further adjustment is needed to lower the support 45 and the blade to follow the downward drift of the coal seam for the purpose Ff removing the maximum height of coal from the mine ace.

During operation of the mining machine 30, where the sensing devices in either the cutter arms 60a, 6% or the cutter arms 65a, 6517 do not provide any signals indicating the presence of material harder than the coal below or above the coal seam, the mining heads 48, 49 and the blade 70 may be adjusted upwardly and downwardly until there are produced signals indicating the location of the relatively harder material, following which the mining heads 48, 49 and the blade 70 may be further adjusted to clear the relatively harder material, and to remove the maximum height of coal from the mine face.

7 Since the signaling system continuously provides signals to the operator at the control station for the mining machine, it is a relatively simple matter for him to make adjustments of the mining mechanisms of the machine as described hereinabove, directed to the purpose of removing the maximum amount of coal from the mine face.

The continuous mining machine is operated and controlled by various hydraulic mechanisms diagrammatically illustrated in FIG. 5, which shows the hydraulic circuits or the machine. The hydraulic system includes a hydraulic head pump 160 which supplies the hydraulic fluid under pressure for operating the cylinder and piston mechanism for raising the mining heads 48, 49, the cylinder and piston mechanism 56 for tilting the mining heads 48, 49, and the cylinder and piston mechanism 57 for separating the mining heads 48, 49 by elevation of the mining head 49 relatively to the mining head 48. The hydraulic pump also supplies hydraulic fluid under pressure for operating various controls in the hydraulic system illustrated in FIG. 5, as will be described in greater detail hereinafter. Another hydraulic pump 161 supplies hydraulic fluid under pressure for operating the hydraulic traction motors 34, 35 which drive the crawler traction treads 32, 33, respectively. A third hydraulic pump 162 supplies hydraulic fluid under pressure for driving the hydraulic motor 83 which operates the conveyor 78. By the use of certain controls in the hydraulic system the hydraulic fluid supplied under pressure by the hydraulic pump 162 can be combined with the hydraulic fluid supplied to the hydraulic traction motors 34, 35 for driving the latter at high speed when the mining machine is being trammed other than in a mining operation. When the hydraulic pump 162 is so used it does not supply any hydraulic fluid to the hydraulic conveyor motor 83. As seen in FIG. 23, each of the hydraulic pumps 160, 161, 162 is mechanically connected to a gear housing 163, which encloses a train of gears for transmitting driving power to the several hydraulic pumps from an electrical motor 164, which drives the gear train in the gear housing 163 and supplies power thereto.

The hydraulic pump 160 supplies hydraulic fluid under pressure through a pressure relief valve 165 to a bank of three solenoid controlled, pilot operated control valves 166, 167, 168. The control valve 166 is connected to the cylinder and piston mechanism 55 for raising the mining heads 48, 49, the control valve 167 is connected to the cylinder and piston mechanism 56 for tilting the mining heads 48, 49, and the control valve 168 is connected to the cylinder and piston mechanism 57 for separating the mining heads 48, 49.

The solenoid controlled, pilot operated control valves 166, 167, 168 are identical, and control valve 166 is illus-' trated in detail in FIG. 6, by Way of example. The control valve 166 comprises a solenoid controlled pilot valve 169 mounted on top of the main control valve 178. The pilot valve 169 comprises solenoids 171, 172 disposed in the opposite ends of the valve 169. The solenoids 171, 172 include armatures 173, 174, respectively, which extend from the solenoids 171, 172 towards the valve spool 175 that is centrally disposed in the valve body 176. The armatures 173, 174 abut the opposite ends of the valve spool 175, and reciprocate the latter, upon energization of one or the other of the solenoids 171, 172, by reciprocation of the corresponding one of the armatures 173, 174. The valve body 176 includes a pressure port 177, which is centrally located in the valve body, and is closed by the valve spool 175 when neither of the solenoids 171, 172 is energized, and the valve spool 175 is in its centered position. Each of the opposite ends of the valve spool 175 has secured thereto a spring guide 178 for a compression spring 179. The compression springs 179 act through the spring guides 178 to maintain the valve spool 175 in its centered position when the solenoids 171, 172 are not energized.

Upon energization of the solenoid 171 the valve spool 175 is reciprocated to the right, as viewed in FIG. 6, whereby the pressure port 177 is connected to the flow port 180. The valve spool 175 also closes the tank port 181 with respect to the flow port 180. In this position of the valve spool 175 the pressure port 177 is closed with respect to the flow port 182, and the latter is connected to the tank port 183. Thus, with the solenoid 171 energized, the flow of hydraulic fluid is from the pressure port 177 through the flow port into the main control valve 170, in which the fluid thus applied acts on the piston end of the valve spool 186, thereby reciprocating the latter to the left, as viewed in FIG. 6. The piston end 187 of the valve spool 186 forces the hydraulic fluid out through the flow port 182 and through the pilot valve 169 to the tank port 183.

When the solenoid 172 is energized, the valvespool 175 is reciprocated to the left, as viewed in FIG. 6, thereby connecting the pressure port 177 to the flow port 182 for supplying hydraulic fluid under pressure to the piston end 187 of the valve spool 186 to reciprocate the latter to the right, as viewed in FIG. 6. The piston end 185 of the valve spool 186 forces the hydraulic fluid out of the main control valve 170 through the flow port 180 and out the tank port 181.

The piston ends 185, 187 of the valve spool 186 each acts as a spring guide for a compression spring 188, which maintain the valve spool 186 in a centered position within the main control valve 170 when there is no hydraulic fluid acting on either of the pistons 185, 187. The main control valve 170 includes a pressure port 189 through which hydraulic fluid under pressure is admitted to the main control valve 170, and a tank port 198 through which hydraulic fluid is exhausted from the control valve 170. The valve spool 186 includes an axially extending central bore 191, and a plurality of radial ports 192 communicating with the bore 191. The radial ports 192 are located in the region of the pressure port 189. In the region of the tank port 198 the valve spool is similarly formed with a plurality of radial ports 193 that communicate with the axial bore 191. With the valve spool in its centered position, as illustrated in FIG. 6, the hydraulic fluid flows from the pressure port 189, through the radial ports 192, into the axial bore 191, and out through the radial ports 193 and the tank port 196, for exhausting of the hydraulic fluid from the main control valve 170.

Upon energization of the solenoid 171 the operation of the pilot valve 169 is as previously described to reciprocate the valve spool 186 to the left, whereby the radial ports 193 are sealed from the tank port 198. The radial ports 192 maintain communication with the pressure port 189, and the hydraulic fluid flows through the axial bore 191 to the radial ports 194, which are in communication with the flow port 195 that is connected by a hydraulic line 196 to one end of the cylinder and piston mechanisms 55 to supply hydraulic fluid under pressure to the latter for operation thereof.

When the solenoid 172 is energized the operation of the pilot valve 169 is as above described to reciprocate the valve spool 186 to the right, as seen in FIG. 6, whereby the tank port is sealed from the pressure port 189, and the latter is directly connected to the flow port 197 for the flow of hydraulic fluid from the pressure port 189 around the valve spool 186 to the flow port 197. Hydraulic fluid under pressure is supplied from the flow port 197 to the cylinder and piston mechanisms 55 through a hydraulic line 198, for operating the cylinder and piston mechanisms 55 by reciprocation thereof.

Each of the cylinder and piston mechanisms 55 is double acting, and when hydraulic fluid is delivered to the cylinder and piston mechanisms 55 through the hydraulic line 196, hydraulic fluid is exhausted from the opposite end of the cylinder and piston mechanisms 55 through the hydraulic line 198. The exhausted hydrau lic fluid is returned to the control valve 170 through flow port 197 which is in direct communication with the tank 9 port 190, and the exhausted hydraulic fluid flows from the flow port 197 around the valve spool 186 and out through the tank port 190.

When hydraulic fluid under pressure is delivered through hydraulic line 198 to one end of the cylinder and piston mechanisms 55, hydraulic fluid exhausts from the other end of the cylinder and piston mechanisms 55 through hydraulic line 196 and enters the control valve 170 through flow port 195. The flow port 195 is in communication with the tank port 190 through radial ports 192, axial bore 191 and radial ports 193, whereby the exhausted hydraulic fluid flows from the flow port 195 to the tank port 190 and is exhausted from the control valve 170.

The hydraulic line 196 includes a check valve 199 Which permits the free flow of hydraulic fluid through the line 196 to the cylinder and piston mechanisms 55, but normally prevents return flow of hydraulic fluid through the line 196, so that the cylinder and piston mechanisms 55 will maintain their adjusted positions. The line 198 is open so that hydraulic fluid can be freely exhausted from the cylinder and piston mechanisms 55 through this line. When hydraulic fluid is delivered under pressure to the cylinder and piston mechanisms 55 through the line 198, this hydraulic fluid under pressure is also communicated through the pilot line 200 to a pilot 201 which operates to open the check valve 199, to permit the exhaust of hydraulic fluid from the cylinder and piston mechanisms 55 through the hydraulic line 196. The pilot 201 includes a return spring 201 for restoring pilot 201 and closing check valve 199.

The solenoid controlled, pilot operated control valves 166, 167, 168 are connected in series, the tank port of the valve 166 being connected to the pressure port of the valve 167, and the latter is similarly connected to the valve 168. Since the pressure port 189 in the control valve 170 of the solenoid controlled, pilot operated control valve 166 is connected to the tank port 190 when neither solenoid 171, 172 is energized, there is a free flow of fluid through the valve 166 to the valve 167, and the same is true as to the flow of hydraulic fluid through the valves 167, 168 when either of the solenoids of these valves is energized. Thus it is seen that any one of the solenoid controlled, pilot operated control valves 166, 167, 168 may be individually operated to adjust the cylinder and piston mechanisms 55, 56, 57, respectively. The hydraulic circuit connecting the control valves 167, 168 to the cylinder and piston mechanisms 56, 57, respectively, is the same as that connecting the control valve 166 to the cylinder and piston mechanisms 55, and operate in the same manner.

The tank port of the solenoid controlled, pilot operated control valve 168 is connected to a hydraulic line 202 which delivers hydraulic fluid under pressure to a solenoid controlled pilot valve 203. The pressure of the hydraulic fluid in the hydraulic line 202 is less than the pressure of the hydraulic fluid delivered to the control valves 166, 167, 168, and is maintained at the lower value by the pressure relief valve 204.

The solenoid controlled pilot valve 203 is illustrated in detail in FIG. 7, and comprises solenoids 205, 206 disposed at the opposite ends of the valve 203. The solenoids 205, 206 have armatures 207, 208, respectively, which extend towards each other into the valve body 209, and abut the opposite ends of the valve spool 210. Each end of the valve spool 210 includes a spring guide 211 for a compression spring 212 that centers the valve spool 210 in the valve body 209 when either solenoid 205, 206 is energized. The valve body 209 includes a pressure port 213 which is closed by the valve spool 210 when the latter is centered in the valve body 209. Upon energization of the solenoid 205, the valve spool 210 is reciprocated to the right by the armature 207, as viewed in FIG. 7, thereby connecting the pressure port 213 to the flow port 214, whereby the hydraulic fluid will flow from the pressure port 213 to the flow port 214. Upon energization of the solenoid 206, the valve spool 210 is reciprocated to the left, as viewed in FIG. 7, by the armature 208, thereby connecting the pressure port 213 to the flow port 215, and flow of the hydraulic fluid will be from the pressure port 213 to the flow port 215. The valve body 209 also includes tank ports 216, 217, and when the pressure port 213 is connected to the flow port 214, the flow port 215 is connected to the tank port 217, and the tank port 216 is closed by the valve spool 210. Similarly, when the pressure port 213 is connected to the flow port 215, the flow port 214 is connected to the tank port 216, and the tank port 217 is closed by the valve spool 210.

The solenoid controlled pilot valve 203 controls and operates a double acting pilot 220 by the selective deliv ery of hydraulic fluid to the latter from either of flow ports 214, 215. When hydraulic fluid under pressure is delivered from one of flow ports 214, 215 to the double acting pilot 220, the other of said flow ports 214, 215 receives the hydraulic fluid which is exhausted from the pilot 220, and this exhausted hydraulic fluid leaves the valve body 209 through a corresponding one of tank ports 216, 217.

A manifold hydraulic line 221 delivers hydraulic fluid under pressure to solenoid controlled pilot valve 222 which is identical to the solenoid controlled pilot valve 203. A manifold tank line 219 connects pilot valves 203, 222 to the tank. The pilot valve 222 operates a double acting pilot 223 in the same manner as the pilot valve 203 operates the pilot 220. The pilot 220 is connected to a reversing valve 224 and the pilot 223 is connected to a similar reversing valve 225. The reversing valves 224, 225 are oppositely disposed, but are otherwise identical and control the direction of operation of the hydraulic traction motors 34, 35, respectively, as will be described in greater detail hereafter.

The manifold hydraulic line 221 also delivers hydraulic fluid under pressure to the solenoid controlled pilot valve 226, which is illustrated in detailed in FIG. 14. The control valve 226 includes two solenoids 227, 228, which are disposed in the opposite ends of the valve 226. The solenoids 227, 228 include armatures 229, 330, respectively, which extend inwardly towards each other and abut the opposite ends of the valve spool 231. Each end of the valve spool 231 includes a spring guide 232 for a compression spring 233, which operate to maintain the valve spool 231 centered within the valve body 234. A pres sure port 235 is centrally disposed in the valve body 234, and is sealed by the valve spool 231 when it is in its centered position. The valve body 234 also includes tank ports 236, 237 disposed at the opposite sides of the valve body 234, and the tank ports 236, 237 are closed by the valve spool 231 when the latter is in its centered position. Upon energization of the solenoid 227, the valve spool 231 is reciprocated to the right, as viewed in FIG. 8, by the armature 229, thereby connecting the pressure port 235 to the flow port 238 for flow of hydraulic fluid from the pressure port 235 to the flow port 238. The tank port 237 is sealed and the flow port 239 is connected to the tank port 236, and any hydraulic fluid exhausting into the flow port 239 is exhausted from the valve body 234 through the tank port 236. Upon energization of the solenoid 228 the valve spool 231 is reciprocated to the left, as viewed in FIG. 8, by the armature 230, whereby the pressure port 235 is connected to the flow port 239, and the tank port 236 is sealed. The flow port 238 is connected to the tank port 237 for the exhaust of hydraulic fluid through the flow port 238 and out the tank port 237.

The solenoid controlled pilot valve 226 operates a pair of double acting pilots 240, 241 which have common connections to the pilot valve 226. The pilot 240 is mechanically connected to a flow control valve 245, and the pilot 241 is similarly mechanically connected to a flow control 

2. IN A MINING MACHINE ADAPTED TO REMOVE MATERIAL FROM A MINE FACE, A FIRST MINING HEAD AND A SECOND MINING HEAD DISPOSED AT THE FRONT OF THE MINING MACHINE ONE ABOVE THE OTHER AND ADAPTED TO BE ADVANCED INTO THE MINE FACE, EACH MINING HEAD INCLUDING MINING MEANS FOR REMOVING MATERIAL FROM THE MINE FACE, HYDRAULIC POSER MEANS FOR RAISING THE MINING HEADS, HYDRAULIC POWER MEANS FOR TILTING THE MINING HEADS, HYDRAULIC POWER MEANS FOR SEPARATING SAID MINING HEADS, A FIRST HYDRAULIC PUMP FOR SUPPLYING HYDRAULIC FLUID UNDER PRESSURE TO EACH OF SAID HYDRAULIC POWER MEANS FOR OPERATING THE LATTER, INDIVIDUAL CONTROL MEANS FOR EACH OF SAID HYDRAULIC POWER MEANS TO CONTROL THE DELIVERY OF HYDRAULIC FLUID TO THE RESPECTIVE HYDRAULIC POWER MEANS EACH CONTROL MEANS INCLUDING SOLENOID MEANS FOR OPERATION OF THE CONTROL MEANS, TRACTION MEANS FOR PROPELLING THE MINING MACHINE AND ADVANCING THE MINING MEANS INTO THE MINE FACE, CONVEYING MEANS FOR CARRYING MINED MATERIAL AWAY FROM THE MINE FACE AND DISCHARGING SAID MINED MATERIAL AT THE REAR OF THE MINING MACHINE, A HYDRAULIC PUMP FOR DRIVING SAID TRACTION MEANS, A SECOND HYDRAULIC PUMP FOR DRIVING SAID HYDRAULIC FLUID UNDER PRESSURE TO THE TRACTION HYDRAULIC MOTOR FOR OPERATING THE LATTER TO DRIVE THE TRACTION MEANS AT LOW SPEED, A HYDRUALIC FLUID VOLUME CONTROL VALVE FOR CONTROL OF THE VOLUME OF HYDRAULIC FLUID DELIVERED TO THE TRACTION HYDRAULIC MOTOR TO VARY THE SPEED OF THE LATTER, HYDRAULIC PILOT MEANS FOR OPERATING THE VOLUME CONTROL VALVE, A PILOT VALVE FOR CONTROLLING THE DELIVERY TO THE DRAULIC FLUID TO THE PILOT MEANS FOR OPERATING THE LATTER, SOLENOID MEANS FOR OPERATING THE PILOT VALVE, A FORWARD AND REVERSE VALVE FOR CONTROLLING THE DIRECTION OF FLOW OF HYDRAULIC FLUID TO THE TRACTION MOTOR FOR OPERATING THE CONTION OF OPERATION THEREOF, HYDRAULIC PILOT MEANS FOR OPERATING THE FORWARD AND REVERSE VALVE, A PILOT VALVE FOR CONTROLLING THE DELIVERY OF HYDRAULIC FLUID TO THE PILOT MEANS TO OPERATE THE LATTER, SOLENOID MEANS FOR OPERATING THE PILOT VALVE, A HYDRAULIC MOTOR FOR OPERATING THE CONVEYING MEANS, A THIRD HYDRAULIC PUMP FOR DELIVERING HYDRAULIC FLUID UNDER PRESSURE TO THE CONVEYING MEANS HYDRAULIC MOTOR FOR OPERATING THE LATTER TO DRIVE THE CONVEYING MEANS, A CONTROL VALVE FOR DIRECTING THE FLOW OF HYDRAULIC FLUID FROM THE THIRD HYDRAULIC PUMP TO THE CONVEYING MEAN HYDRAULIC MOTOR, HYDRAULIC PILOT MEANS FOR OPERATING THE CONTROL VALVE TO DIV ERT THE FLOW OF HYDRAULIC FLUID FROM THE CONVEYING MEANS HYDRAULIC MOTORTO THE FORWARD AND REVERSE VALVE FOR DELIVERY OF HYDRAULIC FLUID FROM BOTH THE SECOND HYDRAULIC PUMP AND THE THIRD HYDRAULIC PUMP TO THE TRACTION MOTOR TO DRIVE THE LATTER AT HIGH SPEED, A PILOT VALVE FOR CONTROLLING THE DELIVERY OF HYDRAULIC FLUID TO THE PILOT MEANS TO OPERATE THE LATTER, SOLENOID MEANS FOR OPERATING THE PILOT VALVE, SAID FIRST HYDRAULIC PUMP SUPPLYING HYDRAULIC FLUID UNDER PRESSURE TO EACH OF THE HYDRAULIC PILOT MEANS THROUGH THE RESPECTIVE PILOT VALVES THEREFOR.
 9. IN A MINING MACHINE ADAPTED TO REMOVE MATERIAL FROM A MINE FACE, A MINING HEAD DISPOSED AT THE FRONT OF THE MINING MACHINE AND ADAPTED TO BE ADVANCED INTO THE MINE FACE, SAID MINING HEAD INCLUDING MINING MEANS FOR REMOVING MATERIAL FROM THE MINE FACE, MEANS FOR ADVANCING SAID MINING HEAD INTO THE MINE FACE, HYDRAULIC POWER MEANS FOR RAISING THE MINING HEAD, HYDRAULIC POWER MEANS FOR TILTING THE MINING HEAD, A HYDRAULIC PUMP FOR SUPPLYING HYDRAULIC FLUID UNDER PRESSURE TO EACH OF SAID HYDRAULIC POWER MEANS FOR OPERATING THE LATTER, INDIVIDUAL HYDRAULIC CONTROL MEANS FOR EACH OF SAID HYDRAULIC POWER MEANS INTERPOSED BETWEEN THE HYDRAULIC PUMP AND EACH HYDRAULIV POWER MEANS TO CONTROL THE DELIVERY OF HYDRAULIC FLUID TO THE RESPECTIVE HYDRAULIC POWER MEANS, EACH HYDRAULIC CONTROL MEANS COMPRISING A HYDRAULIC VALVE FOR CONTROLLING THE FLOW OF HYDRAULIC POWER TO THE RESPECTIVE HYDRAULIC POWER MEANS, PILOT VALVE MEANS SONNECTED TO THE HYDRAULIC VALVE FOR OPERATING SAID HYDRAULIC VALVE, SOLENOID MEANS, FOR OPERATING SAID PIVOT VALVE, MEANS CONNECTING THE HYDRAULIC PUMP TO THE HYDRAULIC VALVE AND TO THE PILOT VALVE TO SUPPLY HYDRAULIC FLUID UNDER PRESSURE TO THE HYDRAULIC VALVE AND TO THE PILOT VALVE FOR OPERATION OF THE HYDRAULIC POWER MEANS AND THE HYDRAULIC VALVE, RESPECTIVELY, SAID INDIVIDUAL HYDRAULIC CONTROL MEANS BEING CONNECTED IN SERIES FOR DELIVERY OF HYDRAULIC FLUID UNDER PRESSURE FROM ONE OF SAID HYDRAULIC CONTROL MEANS TO THE OTHER OF SAID HYDRAULIC CONTROL MEANS. 